Typewriter



. 2 Shets-Sheet 1 c. A. JOERISSEN TYPEWRITER Filed March 15 1952 m \\lll\ I Nov. 15,1932.

Cari J5 Jot/Jew,

-, 1932- I c. A. JOER'ISSE N 1,887,887

TYPEWRITER 7 Filed March 15, 1932 2 Sheets-Sheet 2 Patented Nov. 15, 1932 UNITED STATES PATENT OFFICE CARL A. J'OERISSEN, F WESTFIELD, NEW JERSEY TYIEWRITER The present invention relates generally to means for securing, in typewriters, a substantially noiseless typing stroke. In particular, the invention contemplates type bar actuating mechanism including links connected direct action of the key bar, the result in either event being the general longitudinal displacement .of one of the links through afinal swinging movement of the connecting means to complete a short printing stroke of the type bar.

The invention is susceptible of various embodiments, of which illustrative examples are shown in the accompanying drawings. For the sake of simplicity, the various embodimentsare shown as applied only to a single type bar and associated key bar, it being understood that the illustrated construction is intended to be repeated throughout the machine.

In the drawings F'gure 1 is a cross section through the platen and various structural elements of a machine showing the relation thereto of the type and key bars and the novel transmission mechanism of the present invention, the normal or rest position of the parts being shown.

Figure2 is a view similar to Figure 1 showing in full lines the parts, at the end of the initial throw and in dotted lines the parts in printing position.

Figure 3 is a view similar to Figure 1 showing a modified form of transmission mechanism, the dotted line position being the normal position, and the full line position showing the parts at the end of the initial throw, and

Figure 4 shows a further embodiment of the invention with dotted and full line positions as in Figure 3.

ures 1 and 2, reference numeral 5 designates Referring to the drawings, and first to Fig a platen and reference numerals 6 to 10 structural portions of the machine frame.

' Reference numeral 11 designates a type bar pivoted to element 6 for swinging movements toward and away from the platen and in its normal or rest position the head of thetype lever rests on a pad 12 on a ledge presented by element 7.

A key bar 13 is pivoted to the machine at 14 for oscillation substantially in the plane of the type lever 11, the key lever being sustained in normal rest position by means of a compression spring 15 interposed between the lever and element 10. A bell crank lever 16 is pivoted to element 9 on an axis parallel to the pivotal axis 14 and has a slotted end in which is engaged a pin 17 on the key lever.

A bell crank lever 18 is pivoted to element 8 on an axis parallel to the pivoting axis of the key lever and has an arm connected by means of a turn buckle 19 with the upper arm of lever 16, the ends of the turn buckle having a pivoting connection with the respective lever arms. The other arm of bell crank lever 18 constitutes a link member 20 to the outer end of which is pivoted on a pin 21,

a substantially U-shaped member or lever designated as a whole by the reference numeral 22. Lever 22 comprises an arm 23 extending alongside link 20 and curved into abutment therewith, the abutting relation being yieldingly maintained by a tension spring 24 connected between the arm and the link. Lever 22 also includes an arm 25 extending along the other side of link 20 with its free end spaced from the latter.

A link 26 is pivoted at one end to a lever 22 on a pin 27 and at the other end is in pivotal connection with the type bar 11. Pin 27 is eccentric to pin 21 and the line of the centers of the two pins is at an angle less than a straight angle to link 20.

Upon depression of the key lever an initial movement of the parts is effected, wherein they are brought to the full line position of Figure 2 with links 20 and 26 in substantial parallel relation. While such parallelism at this point is preferable, since it is conditional to the maximumstraightened relation of links 20 and 26 upon movement from normal collapsed position, it may, of course, be departed from more or less. In any event, arm 25 of lever 22 has now come into contact with an abutment rod 28 so that further upward movement of link 20 causes lever 22 to swing about pin 21 so that a substantially longitudinal movement is imparted to link 26 to move the type bar from the full line position of Figure 2 to the dotted line position wherein the type is in printing relation to the platen.

Thus, the type bar is given an initial throw which is terminally checked upon engagement of arm 25 with rod 28 and thereupon lever 22 is swung to complete the type bar movement. Spring 24 serves to holdthe end of arm 23 a ainst link 20 until arm 25 strikes rod 28. T e strength of the spring must be such as to prevent the running away of the type bar under its own momentum at the end of the initial throw. The end of arm 25 is shaped to coact with rod 28 as noiselessly as possible and the rod itself may be made of suitable material or suitably faced to deaden the noise of impact. I

In the embodiment according to Figure 3, links 20a and 26a are pivoted at their adj acent ends to a lever generally designated as 29, pivotal connection being made through pins 30 and 31. The upper angular end 32 of lever 29 extends along arm 20a with its free end in abutment with the latter and yieldingly held in such relation by means of a tension spring 33. The line of the centers of pins 30 and 31 is at an angle less than a straight angle to link 20a and the lever is continued below pin 31 into an arm 34 curved rearwardly of the machine. WVhen upon depression of the key lever the parts are moved from the dotted line position to the full line position and links 20a and 26a have come into substantial parallelism, the end of arm 34 abuts an abutment rod 35 so that the printing stroke is effected. The principle of operation is the same as that described with references to Figures 1 and 2, a principal difference being that according to Figure 3 the abutment rod is below the end of link 20a when the latter has reached the end of its initial throw, whereas according to F gures 1 and 2 the abutment rod is above the end of link 20.

According to Figure 4, a key bar 36 has a fixed pin 37 engaged in the slotted end of a bell crank lever 38, the other end of the bell crank lever being similarly slotted and engaging a pin 39 fixed on the free end of a substantially Z-shaped lever 40 which at its other end is in pivotal connection through a pin 41 with a link 42. A link 43 is pivoted at one end to a type bar 44 and at its other end to lever 40 through a pin 45. A tension spring 46 normally holds the knee portion of lever 40 against link 42 with the centers of pins 41 and at an angle less than a straight angle to link 42.

Upon depression of key bar 36 the parts are moved from the dotted line position to the full line position with the knee of lever 40 always in contact with link 42'. When the links are substantially straightened as in full line position, an abutment foot 47 on link 42 strikes a frame element 48 so that further upward swing of link 42 is prevented. Spring 46 hereupon yields so that continued movement of the key bar causes lever 40 to swing about pin 41. relative to link 42 and thereby impart a substantially longitudinal movement to link 43 to complete the stroke of type bar 44.

It will be noted that in all the described embodiments of the invention, the transmission mechanism includes links having adjacent ends eccentrically pivoted to a connecting element which element has an actuating arm moved either through engagement with a fixed abutment as in Fi ures 1 to 3, or through movement of the key bar directly as in Figure 4.

It is to be understood that the illustrated embod ments are merely indicative of the form which the invention may take and various modifications in detail may be made without departure from the scope of the invention as determined in the following claims.

I claim:

1. In a typewriter, a platen, a type bar 'swingable toward and away from the platen,

and type bar actuating mechanism including a pivoted key bar, a pair of links of which one is pivotally mounted at one end on a fixed machine part and the other is in pivotal connection at one end with the type bar, means connecting the other ends of said links for pivotal movement about different centers with the line of saidcenters normally at an angle less'than a straight. angle to a straight line through the pivot axes of one of the links, depression of the key bar serving to move the links from a collapsed position to a relatively straightened relation whereby to impart to the type bar an initial swing to a position immediately adjacent the platen, and an arm on said connecting means actuated at the end of said initial swim to swing said connectng means and there by impart a longitudinal movement to said type bar connected link to complete the stroke of the type bar.

2. In a typewriter, a platen, a type bar swingable toward and away from the platen, and type bar actuating mechanism including a pivoted key bar, a pair of links of which one is pivotally mounted at one end on a fixed machine part and the other is in pivotal connection at one end with the type bar, means connecting the other ends of said links for pivotal movement about different centers with the line of said centers normally at an angle less than a.

straight angle a straight line through the pivot axes of one of the links, spring means or yieldingly maintaining such normal relation, depression of the key bar serving to move the links from a collapsed position to a relatively straightened relation whereby to impart to the type bar an initial swing to a position immediately adjacent the platen, and an arm on said connecting means actuated at the end of said initial swing to swing said connecting means and thereby impart a ongltudinal movement to said type bar connected link to complete the stroke of the type bar.

3. In a typewriter, a platen, a type bar swingable toward and away from the platen, and type bar actuating mechanism including a pivoted key bar, a pair of links of which one is pivotally mounted at one end on'a fixed machine part and the other is in pivotal connection at one end with the type bar, means connecting the other ends of said links for pivotal movement about different centers with the line of said centers normally at an angle less than a straight angle to a straight line through the pivot axes of one of the links, cooperating abutment portions on said connecting means and the last mentioned one of the links, said abutment portions being normally mutually engaged, depression of the key bar serving to move the links from a collapsed position to a relatively straightened relation whereby to impart to the type bar an initial swing to a position immediately adjacent the platen, and an arm on said connecting means actuated at the end of said initial swing to swing said connecting means and thereby impart a longitudinal movement to said type bar connected link to complete the stroke of the type bar.

4. In a typewriter, a platen, a type bar swingable toward and away from the platen, and type bar actuating mechanism including a pivoted key bar, a pair of links of which one is pivotally mounted at one end on a fixed machine part and the other is in pivotal connection at one end with the type bar, means connecting the other ends of said links for pivotal movement about different centers with the line of said centers normally at an angle less than a straight angleto a straight line through the pivot axes of one of the links, co operating abutment portions on said connecting means and the last mentioned one of the links, said abutment portions being normally mutually engaged, spring means for yieldingly maintaining said engagement, depression of the key bar serving to move the links from a collapsed position to a relatively straightened relation whereby to impart to the type bar an initial swing to a position immediately adjacent the platen, and an arm on said connecting means actuated at the end of said initial swing to swing said connecting means and thereby impart a longitudinal movement to said type bar connected link to complete the stroke of the type bar.

5. In a typewriter, a platen, a type bar swingable toward and away from the platen, and type bar actuating mechanism including a pivoted key bar, a pair of links of which one is pivotally mounted at one end on a fixed machine part and the other is in pivotal connection at one end with the type bar, means connecting the other ends of said links for pivotal 'movement about dillerent centers with the line of said centers normally at an angle less than a straight angle to a straight line through the pivot axes of one of the links, depression of the key bar serving to move the links from a collapsed position to a relatively straightened relation whereby to impart to the type bar in initial swing to a position immediately adjacent the platen, an arm on said connecting means, and a fixed abutment engaged by said arm at the end of said initial swing to swing said connecting means and thereby impart a' longitudinal movement to said type bar connected link to complete the stroke of'the type bar.

6. In a typewriter, a platen, a type bar swingable toward and away from the plat en, and type bar actuating mechanism including a pivoted key bar, a pair of links of which one is pivotally mounted at one end on a fixed machine part and the other is in pivotal connection at one end with the type bar, means connecting the other ends of said links for pivotal movement about different centers with theline of said centers normally at an angle less than a straight angle to a straight line through the pivot axes of one of the links, depression of the key bar serving to move the links from a collapsed position to a relatively straightened relation whereby to impart to the type bar an initial swing to a position immediately adjacent the platen, and an arm on said connecting means acted on by the key bar at the end of said initial swing to swing said connecting means and thereby impart a longitudinal movement to said type bar connected link to the complete stroke of the type bar. f;

7. In a typwriter, a platen, a type bar swingable toward and away from'the platen, and type bar actuating mechanismii-ncluding a pivoted key bar, a pair of links of which one isin connection at one end with the kev bar and the other is in connection at one end with the type bar, and a lever to which the otherehds ofsaid links are pivoted at spaced points with the line of said points normally at an angle less than a straight angle to a straight line through the pivot axes of the key bar connected link, depression of the key bar serving to move the links from a collapsed position to a relatively straightened re ation whereby to impart to the type bar an initial swing to a position immediately adjacent the platen, said lever including an arm extending alongside the key bar connected link and actuated at the end of said initial swing to swing said lever and thereby impart a longitudinal movement to said type bar connected link to complete the stroke of the type bar.

8. In a typewriter, a platen, a type bar swingable toward and away from the platen, and type bar actuating mechanism including a pivoted key bar, a first link in connection at one end with the key bar, a second link in connection at one end with the type bar, a lever to which the other ends of said links are pivoted on spaced centers with the line of said centers normally at an angle less than a straightangle to a straight line through the pivot axes of said first link, depression of the key bar serving to move the links from a. collapsed position to a relatively straightened relation whereby to impart to the type bar an initial swing to a position immediately adjacent the platen, said lever includin an angular arm, and an abutment engage by the arm at the end of said initial swing whereby the lever is caused to swing relative to said first link to impart a longitudinal movement to said second link and thereby complete the stroke of the type bar.

9. In a typewriter, a platen, a type bar swingable toward and away from the platen, and type bar actuating mechanism including a first link pivoted at one end to a fixed element of the machine, a second link pivoted at one end to the type bar, a lever connecting the other ends of said links for pivotal movement about spacedcenters whose line is normally at an angle less than a straight angle to a straight line through the pivot axes of said first link, spring means yieldingly maintaining such normal relation, said lever including an arm in connection with the key bar, depression of the key bar acting through said lever and spring means to move the links from a collapsed position to a relatively straightened relation whereby to impart to the type bar in initial swing to a position imn'iediately adjacent the platen, and abutment means arresting said first link whereby continued depression of the key bar causes swinging of said lever relative to said first link and consequent longitudinal movement of said second link to complete the stroke of the type bar.

In testimony whereof I aflix my signature.

CARL A. JOERISSEN. 

